Telephone-exchange system



H. P. CLAUSEN. TELEPHONE EXCHANGE SYSTEM. 'APPUCATION FILED MAR-2|,1917- L n 9 0 5 8 n a M. Z MP P KL H y H $2 w R b I|| N NW c E QM J. L qM ll. N & J Jo W UNITED STATES PATENT OFFICE.

HENRY P. CLAUSEN, OF MOUNT VERNON, NEW YORK, ASSIGNOR TO WESTERN ELEC-TRIO COMPANY, INCORPORATED, OF NEW YORK, N. Y., A CORPORATION OF NEWYORK.

TELEPHONE-EXCHAN GE SYSTEM.

Specification of Letters Patent.

Patented Oct. 18, 1921.

Application filed March 21, 1917. Serial No. 156,293.

To all whom z't may concern:

Be it lmown that I, HENRY P. CLAUsnN, a citizen of the United States,residing at Mount Vernon, in the county of VVestchester and State of NewYork, have invented certain new and useful Improvements inTelephone-Exchange Systems, of which the following is a full, clear,concise, and exact description;

This invention relates to telephone exchange systems, and moreparticularly to signaling in such systems.

It is the object of this invention to provide an arrangement foroperatinga signal in a distinctive manner when the called subscriberanswers.

In systems in which connection is established through the agency of anoperator, and more especially in private branch exchange systems, itwill frequentl occur that the operator will inform the cal ingsubscriber that he may replace his receiver and that she will call himwhen the called party answers.

. If the operator is provided only with supervisory signals of the usualcharacter, the result will be that after connection to the wanted linehas been established and ring ing has been started, she may attend toanother connection. The called subscribers supervisory lamp will belighted at this time, and upon the called subscribers answer, hissupervisory lamp will be extinguished. Should the operator fail tonotice the extinguishing of this lamp, it is quite likely that she willnot at once notice such answer, since the supervisory lamp is now in itsnormal condition, that is, extinguished.

It is then, more specifically, the object of this invention to cause asignal to be operated in a distinctive manner to attract the op eratorsattention when the called subscriber answers.

It is a further object of the invention to provide means whereby acalling subscriber may be signaled distinctively when the called partyanswers. By means of this arrangement, in case the calling subscriberdoes not wish to await .the reply of the called subscriber, he may putdown his receiver and need pay no further attention to the call untiladvised by the operation of the signal that his call has beensuccessfully established.

A feature of the invention is an arrangement in which a special signalis operated, in a system in which an operator establishes connectionover a train of automatic switches, a current reversal being utilized tooperate a polarized relay controlling such distinctive signal.

A further feature of the invention is the provision of means to utilizesuch current reversal to operate a signal at a calling subscribersstation if the receiver at said station is removed from the receiverhook.

Other features will be more clearly understood by reference to theaccompanying drawing, in which there is diagrammatically shown only somuch of a semi-automatic system as is deemed necessary to anunderstanding of the invention.-

It is believed that the invention will best be understood by tracing aconnection from a calling substation A to a substation B at some otherexchange.

When the subscriber at substation A removes his receiver, a circuit forline relay LR is completed. The operation of this relay closes a circuitfor line lamp 1. The operator upon observing the lighted lamp insertsthe answering plug P in the jack J of the calling line, and operates thetalking keys TK, which connect the operators head set HS to the callingline. The insertion of the plug P into the jack J also completes acircuit for cut-off relay G0, which opens the circuit of line relay LR,causing lamp 1 to be extinguished in the well-known manner.

The operator, upon ascertaining the wanted number, operates theconnecting keys CK to separate them from their inner contacts, openstalking keys TK, and closes the keys 10 and 11, which closes a circuitfor a first selector (not shown) to move the brushes 3, 4 and 5 intoengagement with an idle connector.

WVhen connection is made to an idle connector a circuit is completed forrelays 15 and 16 from grounded battery, relay 15, conductor 17, contact18, conductor 19, terminal 7, brush 3, conductor 20, key 10, conductor43, sender S, conductor 46, key 11, conductor 47, brush 4, terminal 6,conductor 24, contact 25, conductor 26, relay 16, to ground. Relay 16,by attracting its armature closes a circuit for slow release magnet 48from grounded battery, release magnet 48, conductor 49, armature andfront contact of relay 16 to ground. This magnet 48 is made slow torelease its armature so that it remains energized during thetransmission of the impulses and until the calling line circuit isopened for a rela tively long period of time, as is well-known in theart.

The operator now operates the sender S in the usual manner to transmitimpulses corresponding to the wanted number, causing the brushes '12, 13and 14 of the connector to engage the terminals of the wanted subscriberThe connector circuit may be. similar to that shown in patent to B. D.Willis, 1,156,450, issued October 12, 1915, and only such portions havebeen shown as are deemed necessary for an understanding of thisinvention. \Vhen the brushes 12, 13 and 14 engage the terminals of thesubscribers line B, the line is tested and, if found idle, ringingcurrent is applied.

The operator then opens keys 10 and 11,

which disconnects her head set from the wanted line, and presses theholding keys HK, which connect relay 14 in series with relays 15 and 16over the following circuit: grounded battery, relay 15, conductor 17,contact 18, conductor 19, terminal 7, brush 3, conductor 20, upperholding key HK, conductor 21, polarized relay 14, conductor 22, lowerholding key HK, conductor 23, brush 4, terminal 6, conductor24, contact25, conductor 26, relay 16, to ground. Relay 14 does not becomeenergized, as the current flow through its winding is in the oppositedirection to that required for its energization.

When the subscriber at substation B answers by taking his receiver offthe hook, relay 27 becomes energized from grounded battery, upperwinding of relay 27, conductor 28, connector brush 13, terminal 29,subscriber Bs substation apparatus, terminal 30, connector brush 14,conductor 31, lower winding of relay 27, to ground. Relay 27 thereuponattracts its armatures, which breaks the circuit through contacts 18 and25, respectively, and closes the following circuit: grounded battery,relay 15, conductor 32, lower armature and front contact of relay 27,conductor 24, terminal 6, brush 4, conductors 47 and 23, lower holdingkey HK, conductor 22, relay 14, conductor 21, upper holding key HK,conductor 20, brush 3, terminal 7, conductor 19, upper armature andfront contact of relay 27, conductor 26, relay 16, to ground. Thiscurrent flow is in a direction to cause the energization of relay 14,which closes a circuit for lamp 33, from grounded battery, lamp 33,conductor 34, contact 35, conductor 36, armature and front contact ofrelay 14, conductor 37, interrupter 38 to ground. The lamp 33 therebyproduces a flashing signal in front of the operator.

The operator upon seeing the flashing signal then knows that the calledparty has answered and so completes the connection between the callingand the wanted subscriber by operating the connection keys CK so as toengage their outer contacts. If subscriber A has replaced his receiverupon the hook the operator will operate ringing keys Rli to ring thesubscriber A to recall him to his telephone. If, however, the callingparty has merelyput down his receiver while waiting for the called partyto answer, he receives a signal notifying hint that -the called partyhas answered. This signal is controlled by a polarized relay 40connected in series with the line circuit and which is energized as soonas the operator presses keys CK to complete the connection between thecalling and called subscribers. 2 Relay 40 attracts its armature 41which engages the bell 42, or operates any other well-known signal, togive the desired information;

After completing the connection the operator releases the holding keysHK to separate them from their contacts, which opens the circuitofrrelay 14 which in turn opens the circuit of lamp 3 3.

What is claimed is: V

1. In a telephone exchange system, the combination with telephone lines,substations therefor, an operators connecting circuit forinterconnecting said lines, a circuit at the calling substationincluding contacts closed in the alternate position of the receiver hookthereat, a signaling device in said circuit, means for preparing anactuating circuit for said device controlled by the called subscriber,and manual means in the operators connecting circuit for completing saidactuating circuit.

2. In a V telephone exchange system, the combination with telephonelines, substations therefor, automatic switches, a sender for settingsaid switches to interconnect said lines, a circuit at the callingsubstation including contacts closed in the alternate position of thereceiver hook thereat, a signaling device included in said circuit,means for preparing an actuating circuit for said device controlled bythe called subscriber, and means actuated after the talking connectionis established-for closing said actuating circuit.

3. In a telephone exchange system, the combination with telephone lines,substations therefor, an operators connecting circuit forinterconnecting said lines, a circuit at the calling substationincluding contacts closed in the alternate position-of the receiver hookthereat, a signaling device in said circuit, a supervisory lamp in saidconnecting circuit, means for flashing said lamp when the called partyresponds, and a key insaid connecting circuit thereupon actuated by theoperator for operating said substation signal.

4. In a telephone exchange system, a private branch exchange, a manualboard thereat, telephone lines terminating therein, substationsincluding calling sets included in said lines, connecting circuitsincluding automatic switches associated with said board, a. sender atsaid board for controlling said switches to interconnect said lines, asignaling device at the calling substation connected to the talking setthereat, a supervisory lamp in said connecting circuit, means forflashing said lamp when the called party re- 10 spends, and a key insaid connecting circuit In witness whereof, I hereunto subscribe 15 myname this 20th day of March, A. l). 1917.

HENRY P. CLAUSEN.

